[turbofan] Remove representation axis for float64 fields.

src/compiler/js-native-context-specialization.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler/js-native-context-specialization.h"
 
 #include "src/accessors.h"
 #include "src/code-factory.h"
 #include "src/compilation-dependencies.h"
 #include "src/compiler/access-builder.h"
@@ skipping 878 matching lines @@
     if (!field_index.is_inobject()) {
       storage = effect = graph()->NewNode(
           simplified()->LoadField(AccessBuilder::ForJSObjectProperties()),
           storage, effect, control);
     }
     FieldAccess field_access = {
         kTaggedBase, field_index.offset(),     name,
         field_type,  MachineType::AnyTagged(), kFullWriteBarrier};
     if (access_mode == AccessMode::kLoad) {
       if (field_type->Is(Type::UntaggedFloat64())) {
+        // TODO(turbofan): We remove the representation axis from the type to
+        // avoid uninhabited representation types. This is a workaround until
+        // the {PropertyAccessInfo} is using {MachineRepresentation} instead.
+        field_access.type = Type::Union(
+            field_type, Type::Representation(Type::Number(), zone()), zone());
         if (!field_index.is_inobject() || field_index.is_hidden_field() ||
             !FLAG_unbox_double_fields) {
           storage = effect = graph()->NewNode(
               simplified()->LoadField(field_access), storage, effect, control);
           field_access.offset = HeapNumber::kValueOffset;
           field_access.name = MaybeHandle<Name>();
         }
         field_access.machine_type = MachineType::Float64();
       }
       value = effect = graph()->NewNode(simplified()->LoadField(field_access),
                                         storage, effect, control);
     } else {
       DCHECK_EQ(AccessMode::kStore, access_mode);
       if (field_type->Is(Type::UntaggedFloat64())) {
+        // TODO(turbofan): We remove the representation axis from the type to
+        // avoid uninhabited representation types. This is a workaround until
+        // the {PropertyAccessInfo} is using {MachineRepresentation} instead.
+        field_access.type = Type::Union(
+            field_type, Type::Representation(Type::Number(), zone()), zone());
         value = effect = graph()->NewNode(simplified()->CheckNumber(), value,
                                           effect, control);
 
         if (!field_index.is_inobject() || field_index.is_hidden_field() ||
             !FLAG_unbox_double_fields) {
           if (access_info.HasTransitionMap()) {
             // Allocate a MutableHeapNumber for the new property.
             effect = graph()->NewNode(
                 common()->BeginRegion(RegionObservability::kNotObservable),
                 effect);
@@ skipping 560 matching lines @@
 }
 
 
 SimplifiedOperatorBuilder* JSNativeContextSpecialization::simplified() const {
   return jsgraph()->simplified();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8